1. Field of the Invention
This invention relates to process for preparing alkali metal salts of carbazole having high purity.
2. Description of the Prior Art
The alkali metal salts of carbazole are important as intermediates for the preparation of vinyl carbazole. Known methods for preparing the alkali metal salts of carbazole include, for example, a method which involves subjecting carbazole to an alkali fusion (Japanese Pat. No. 170,858), or a method wherein carbazole is reacted with metallic sodium in the presence of gasseous ammonia at an elevated temperature and an elevated pressure (Japanese Pat. No. 169,946). These conventional methods, however, suffer from the disadvantage that not only are there difficulties in the alkali fusion or the use of a high pressure reaction, but also the alkali salt of carbazole produced has a black brown color and is poor in purity to an extent that it is unsuitable as a starting material to prepare vinyl carbazole to be used in preparing modern day electrophotographic materials.
It is an object of this invention to provide a process for preparing alkali metal salts of carbazole, which can be operated safely and easily industrially. Another object of this invention is to provide a process for preparing alkali metal salts of carbazole useful for producing vinyl carbazole of high purity suitable for use in electrophotography.